Need help with clothing my character mesh
Lets see if this helps.

 


Select all the faces of the mesh your want to make clothes for.
I did face select, then i highlighted all the faces. (Photo above)





Duplicate that mesh by hitting 'Shift + D', then press 'enter'. After this you want to scale the mesh by going to your tools manu and hitting the 'scale', 'shrink/fatten', or 'push/pull' tab. (photo above and below)





To make the mesh "baggy" or thicker you can add a modifier like 'solidify'. (photo below)





change the 'thickness' value to get the desired results. (photo below)

these were my results.(photo below)

Thats it! now just shape your clothes to the desired shape and/or add a subdivision surface modifier to make it smoother. Then if you want you can sculpt the clothing, but thats all up to you.